The present invention relates generally to operations performed and systems utilized in conjunction with subterranean wells and, in an embodiment described herein, more particularly provides a method of reservoir characterization based on detection of displacements at the earth's surface.
Many benefits may be realized by having the capability of accurately determining characteristics (such as volume, permeability, shape, location, presence, etc.) of a reservoir. For example, optimal locations for drilling infill wells in a field, optimal production and/or injection rates and other useful information may be determined once the reservoir characteristics are reasonably well known.
Further benefits may be realized if the reservoir characteristics can be evaluated without flowing reservoir fluid to the surface as is done in typical drill stem tests. For example, environmental hazards, safety hazards, the cost of transporting drill stem testing equipment and crews to drilling sites, etc. may be reduced or eliminated if reservoir fluid is not flowed to the surface.
Still further benefits may be realized if reservoir characteristics can be known, or at least predicted with acceptable accuracy, without drilling into the reservoir. For example, the substantial cost of drilling could be avoided if the predicted reservoir characteristics do not justify the drilling cost; or the drilling location could be optimized to produce a maximum return on investment.